Doodad

From The StarCraft 2 Wiki

A doodad in Blizzard games is usually a special part of the terrain, such as a rock, branch, bridge, building or crashed space vehicle. It can also be something organic, like a bush or a tree. The general explanation is that it's an "object" on the map that isn't a unit or a (gameplay) building.

As an additional example in StarCraft I, the opening and closing doors in the Installation Tileset were doodads that required specific triggers to open and close.

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